Dear David Sainsbury: The mother of a Sainsbury checkout operator asks the the supermarket chief to give her son a break - and a complimentary cup of coffee

I'm not going to whinge on about how rich you are. Being worth pounds 1.38bn, as announced yesterday by BusinessAge, can't be all fun. People bang on at you for hand-outs for a start. Anyway, I'm sure you've earned it. You probably started off with a Saturday job just like the rest of us. What was it? Petrol pump attendant? Cold forecourts and a grubby office with a telly the size of your thumbnail. At least you didn't have to wear a frilly white apron to wait on grumpy retired couples in the Dorothy Tearooms. Or were you lucky, something a bit more upmarket - a stint in your local shop perhaps?

My son, aged 18, works in one of your shops at the weekends. I encouraged him to apply. It seemed a doddle to me - air conditioning, higher Sundays rates, even the uniform is well, roomy, though I must say polyester shirts are a bit of a naff choice (do you wear polyester on a hot day?).

Since he's been there, mainly on checkout duty, my relationship with all checkout assistants has changed. I look at them. We exchange pleasantries. They often look tired and fed-up. I sympathise. You see I think they get a rough deal. I'm bargaining on you being on an altruistic high this week - feted as the second richest in the land - to sort this one out.

Let me explain. Some of your staff are sitting at your supermarket tills for four hours at a time without a break. This is not illegal in this country. That doesn't surprise me. But think about it. Can you remember a morning recently when you sat at your desk, with no more movement than a swivel action on your buttocks for four whole hours? You couldn't stand up, stretch or walk to the window. No chance of a coffee either and no access to a loo unless you press a buzzer and make a fuss about your bladder not being up to it.

And then imagine having to face long queues, a human conveyor belt with big trolleys stopping in front of you offloading heavy cartons of beer, leaky bags of fish and a whole range of veg for which to memorise four-figure codes to get up speed.

Some people smell, some aren't wearing more than swimming trunks, so that your eye hits their navel as you pass those delicious tartes aux pommes you do so well over the scanner. Some have forgotten all their money, only they don't discover that until you've punched in 67 items and there are six people waiting. And through all of this you are supposed to smile.

Come on, do the decent thing and pick up the phone. The Sainsbury group is hardly broke; before tax and one-off costs you made pounds 738m last year. Give your staff on checkout duty a break every couple of hours. Paid. With complimentary coffee.